I recommend you try the Gutenprint driver set from:
Just to show you there are options, there is also the hpijs 3-part/download driver from here:
The only issue I can see is they don't show as working for OS 10.9 Maverick. They both stop at 10.8 Mountain Lion.
Is there a longshot possibility it would work anyway, or are they so different that they won't likely work?
PS Thank you for the QUICK reply! I didn't expect to hear anything for ages! Cheers!